Table of Contents
Note: This API call is for DOS and Win16 personality only. Use Family API for portability.
Int 21H, AH=45H
Version
2 and higher
Brief
“DUP” - DUPLICATE FILE HANDLE
Family API
Input
- AH = 45h
- BX = file handle
Return
- CF clear if successful
- AX = new handle
- CF set on error
- AX = error code (04h,06h) (too many open files (no handles available), invalid handle)
Notes
moving file pointer for either handle will also move it for the other, because both will refer to the same system file table
for DOS versions prior to 3.3, file writes may be forced to disk by duplicating the file handle and closing the duplicate
See also
Note
Text based on Ralf Brown Interrupt List Release 61
| osFree Macro Library | |
|---|---|
| Video I/O | @SetMode @SetCurSz @SetCurPos @GetCur @SetPage @ScrollUp @ScrollDn @Scroll @GetChAtr @PutChAtr @PutCh @SetPalet @SetColor @SetDot @GetDot @WrtTTY @VideoState @GetMode @GetDisplay @GetVideoState @GetEGAInfo @Cls |
| Hardware info | @Equipment @MemSize |
| Serial I/O | @AuxInit @AuxSendChar @AuxRecieveChar @AuxStatus |
| Tape I/O | @TapeOn @TapeOff @TapeRead @TapeWrite |
| Keyboard I/O | @KbdStatus @CharIn @CharPeek |
| Printer I/O | @PrnPrint @PrnInit @PrnStatus |
| Disk I/O | @DskReset @DskStatus @DskRead @DskWrite @DskVerify @DskFormat |
| Date and Time | @SetTime @GetTime |
| Mouse | @MouInit @MouShowPointer @MouStatus @MouSetPos @MouSetMickey @MouRegion |
| Memory manager | @ModBlok SET_BLOCK |